The present invention relates to vehicle suspension systems, and pertains more particularly to an automotive suspension system in which a composite elongate member, which functions as a spring and a control arm, has a dihedrel for establishing a pre-load of the spring for establishing the ride height of the vehicle.
Vehicle suspension systems have heretofore included shock absorbers, springs (coil, leaf, air or torsion bar), axle housing, torque arms, A-frames, anti-roll bars, stabilizers, and so forth. These components have been assembled in various combinations in an effort to produce the desired ride and handling characteristics of the vehicle.
In a typical suspension system, changes in the spacing between axles and the body/chassis due to uneven road and other similar conditions are cushioned by springs. System oscillations are limited by dampers which are usually called shock absorbers. The shock absorbers dissipate the energy stored in the springs by gradually forcing oil through restrictive orifices and valves. The flow resistance encountered by the oil results in compression and rebound forces which control the spring movement. The work done by the oil as it moves through the valves converts energy stored in the springs into heat which is dissipated from the shock absorbers into the surrounding air.
There is a continuing effort to reduce the manufacturing cost of automobiles. There is also a continuing effort to increase the mileage of automobiles through weight reduction. Both of the aforementioned efforts must not unduly sacrifice performance, road handling or reliability. Conventional suspension systems tend to have numerous expensive heavy metal parts. It is, therefore, desirable to reduce the cost, weight and complexity of existing suspension systems.
Automobile suspension systems have heretofore been provided which have incorporated composite leaf springs. See for example U.S. Pat. Nos. 4,540,197 and 4,557,500. These composite leaf springs have been constructed by molding glass or other reinforcing fibers and a resin or other binder into the desired shapes. Typically, such composite leaf springs have been made of a plurality of laminations. They have been molded or otherwise constructed with a particular curvature so that they assume a desired configuration under normal loading conditions. Thus, these types of composite leaf springs are relatively complex and expensive to construct.
In my prior applications I disclose a number of different composite suspension system structures. In those systems, a composite member served the dual function of a spring and a control arm.
It would be desirable to provide a vehicle suspension incorporating less expensive composite springs. Such a suspension system would also preferably incorporate a sway bar to limit body roll during cornering.